- Discovered in 1917 by French Canadian biologist Félix d’Hérelle, phages – or bacteriophages – are tiny viruses that are natural predators of bacteria.
- In many countries they were supplanted during the Second World War by antibiotics but continued to be used for decades in Eastern Europe.
- They are now being seen by some scientists as a complement – and perhaps an alternative –to antibiotics, the overuse of which has led to increasing bacterial resistance and the advent of the superbug.
- Unlike antibiotics, phages must be used in a highly targeted way, because each phage is effective against only a limited number of bacteria.
- They have, undergone important therapeutic and commercial development.
- In the near future, phages will be secondary to antibiotics as they can still work against most pathogens. Phages will be the last option when you have no choice.
- According to the World Health Organization (WHO), antimicrobial resistance is a rising threat to global health, jeopardising decades of medical progress and transforming common infections into deadly ones.
- A UN report published last year suggested yearly deaths from drug-resistant diseases could rise from the current 700,000 to 10 million in 30 years if no action is taken.
- In principle, phages are cheaper and quicker to develop than conventional drugs, can be designed to minimise future bacterial resistance and have no reported side-effects.
- There are downsides – phages are slower than antibiotics.
- Not readily available, they cannot be used in an emergency setting and time is usually needed to find the right phage to target the relevant bacteria.
- They have a narrow spectrum and are less stable than chemical drugs.
- Phage therapy tends to be used in a personalised way which makes comparisons difficult and it is likely they are more efficient against certain bacteria, while antibiotics are more efficient against others, so new studies suggest it is better to combine both.
- Phage therapy centres such as the ones that exist in Poland and Georgia claim to have a success rate of 75-85%.
- More research is needed to know if phage use has any negative effect on the human body, but so far few side-effects have been reported.
- While producing phage-based drugs for food decontamination is already possible in some countries, the development of phage therapy for human health faces bigger hurdles.
- The lack of clinical trials meeting international standards means that – outside the former Soviet bloc – access to phages is either nonexistent or restricted to compassionate use. Many countries lack an appropriate regulatory framework.
